1. Field of the Invention
The invention relates generally to network bandwidth usage analysis, management and control, and more specifically to methods and circuits for measuring and/or limiting the real-time bandwidth usage of individual internet protocol addresses.
2. Description of the Prior Art
Internet access bandwidth is both a critical resource and a key cost factor for Internet service providers (ISP's) in particular. Reliable bandwidth usage auditing and monitoring is important in two types of web hostings offered by ISP's, i.e., "co-location" and "dedicated/shared-server" services.
In co-location service, a customer owns a dedicated web server located at an ISP's facility and purchases Internet bandwidth from the ISP. The ISP buys bandwidth in bulk and resells it to each customer. To do this best, accurate auditing and monitoring of the bandwidth usage by each web hosting customer is needed. ISP's without bandwidth usage tools charge for average bandwidth or peak usage.
In dedicated-server service, customers rent dedicated servers that are owned and maintained by the ISP. In shared-server service, customers rent disk space, and share CPU and ETHERNET bandwidth with other web site customers on the ISP's equipment. While this provides a low cost service for the customer, it frequently results in an overcrowding of the equipment and long delays or inaccessibility of the sites sharing the server. When the ISP has a clear picture of usage patterns, users can be relocated onto servers that do not clash with other users, or changed to dedicated-server service.
The web hosting business is becoming increasingly competitive. Customers are demanding guaranteed service and accountability for the access bandwidth charges by their ISP's. The customers too would welcome the ability to monitor their own usage patterns in real time. ISP's need to differentiate their services and provide a guaranteed quality of service to ensure customer satisfaction. In addition, unlike hit-rate data provided by other software, bandwidth usage patterns give web site owners a different angle for gauging responses to changes in content on their sites.
From a strategic standpoint, real-time bandwidth monitoring is important for the ISP's to determine if sufficient bandwidth is being purchased, to plan the growth of the network, and to analyze unusual bandwidth patterns which may signify problems with the server or the ISP's equipment.
A prior art pure-software approach to bandwidth management implements a priority-based queuing algorithm completely in UNIX or WINDOWS. These implementations usually have too much operating system overhead and its throughput rarely exceeds 1,000 Kb/s. A prior art pure hardware approach implements a control algorithm in logic. But only very simple algorithms are practical, such as packet counting and dropping when a bandwidth limit is reached. Such a simple-minded approach can drop too many packets unnecessarily, which results in massive re-transmission on the Internet. Instead of providing Quality of Service on the Internet/Intranet, it actually degrades the network. In the pure hardware approach, new features, such as an implementation of Internet Protocol version six (IPv6), generally require replacement of hardware equipment. A third prior art approach allows a bandwidth management device to change a customer's packets in order to slow down the sender. It creates a new variable in end-to-end TCP/IP flow control mechanism, and its effect on the Internet traffic is not well understood. The effectiveness of this depends on the implementation of hundreds of different TCP/IP stacks currently in use.
Internet access bandwidth is both a critical resource and a key cost factor for ISP's in particular. Reliable bandwidth usage auditing and monitoring is important in web hosting businesses. ISP's proactively allocate appropriate bandwidth among competing sources, and charge their customers according to their actual bandwidth usage. Real-time and historical bandwidth data is critical for planning the network growth.